This invention relates to apparatus for controlling the hydroplanes of marine vessels and has particular, but not exclusive, application to hydroplanes for submarines.
Control apparatus for submarines has previously been proposed wherein port and starboard hydroplanes are each mounted on the outer end of a stock carrier on a crosshead. Each crosshead is slidably mounted on guide rails and the inner end of each stock is externally splined to co-operate with the internal splines of a common driving sleeve so that the stock can slide axially relative to its driving sleeve but cannot rotate relative thereto. Each driving sleeve is connected to a tilt lever mechanism through a torque tube for effecting angular movement of the sleeve about its axis in order to tilt the hydroplane mounted at the outer end of its associated stock. The tilt lever mechanism is actuated by an hydraulic piston and cylinder unit.
Extending between the port and starboard crossheads is a main hydraulic piston and cylinder which can be hydraulically actuated to enable the crossheads to be moved in and out of their guide rails thus effecting extension and retraction of the hydroplanes. During such extension or retraction, the external splines of the stocks slide relative to the associated internal splines of their respective sleeves. Tilting of each hydroplane is effected by actuating the tilting cylinder to operate the tilting lever assembly and cause the port and starboard torque tubes to be rotated. This causes rotation of the internally-splined sleeves and, due to the splines, rotation of the stocks and hydroplanes.
Hydraulic locking mechanisms are provided to enable the hydroplanes to be locked in predetermined positions of tilt (e.g. 16.degree. and 0.degree. respectively) as well as in extended or retracted positions.
The above-described apparatus has a disadvantage in that its components are required to be formed of a high tensile, non-ferrous material because they are located outside the pressure hull of the vessel and are continually immersed in sea water. A further disadvantage is that accurate athwartship alignment of the crossheads is required. For this reason, among others, the manufacturing costs are high.